Skip to content

Commit

Permalink
h8300: clock driver
Browse files Browse the repository at this point in the history
Signed-off-by: Yoshinori Sato <[email protected]>
  • Loading branch information
ysat0 committed Jun 23, 2015
1 parent 8dbdef2 commit 7b5bb89
Show file tree
Hide file tree
Showing 6 changed files with 250 additions and 0 deletions.
Original file line number Diff line number Diff line change
@@ -0,0 +1,24 @@
* Renesas H8/300 divider clock

Required Properties:

- compatible: Must be "renesas,sh73a0-h8300-div-clock"

- clocks: Reference to the parent clocks ("extal1" and "extal2")

- #clock-cells: Must be 1

- reg: Base address and length of the divide rate selector

- renesas,width: bit width of selector

Example
-------

cclk: cclk {
compatible = "renesas,h8300-div-clock";
clocks = <&xclk>;
#clock-cells = <0>;
reg = <0xfee01b 2>;
renesas,width = <2>;
};
Original file line number Diff line number Diff line change
@@ -0,0 +1,23 @@
Renesas H8S2678 PLL clock

This device is Clock multiplyer

Required Properties:

- compatible: Must be "renesas,h8s2678-pll-clock"

- clocks: Reference to the parent clocks

- #clock-cells: Must be 0

- reg: Two rate selector (Multiply / Divide) register address

Example
-------

pllclk: pllclk {
compatible = "renesas,h8s2678-pll-clock";
clocks = <&xclk>;
#clock-cells = <0>;
reg = <0xfee03b 2>, <0xfee045 2>;
};
1 change: 1 addition & 0 deletions drivers/clk/Makefile
Original file line number Diff line number Diff line change
Expand Up @@ -73,3 +73,4 @@ obj-$(CONFIG_ARCH_U8500) += ux500/
obj-$(CONFIG_COMMON_CLK_VERSATILE) += versatile/
obj-$(CONFIG_X86) += x86/
obj-$(CONFIG_ARCH_ZYNQ) += zynq/
obj-$(CONFIG_H8300) += h8300/
2 changes: 2 additions & 0 deletions drivers/clk/h8300/Makefile
Original file line number Diff line number Diff line change
@@ -0,0 +1,2 @@
obj-y += clk-div.o
obj-$(CONFIG_H8S2678) += clk-h8s2678.o
53 changes: 53 additions & 0 deletions drivers/clk/h8300/clk-div.c
Original file line number Diff line number Diff line change
@@ -0,0 +1,53 @@
/*
* H8/300 divide clock driver
*
* Copyright 2015 Yoshinori Sato <[email protected]>
*/

#include <linux/clk.h>
#include <linux/clkdev.h>
#include <linux/clk-provider.h>
#include <linux/err.h>
#include <linux/of.h>
#include <linux/of_address.h>

static DEFINE_SPINLOCK(clklock);

static void __init h8300_div_clk_setup(struct device_node *node)
{
unsigned int num_parents;
struct clk *clk;
const char *clk_name = node->name;
const char *parent_name;
void __iomem *divcr = NULL;
int width;

num_parents = of_clk_get_parent_count(node);
if (num_parents < 1) {
pr_err("%s: no parent found", clk_name);
return;
}

divcr = of_iomap(node, 0);
if (divcr == NULL) {
pr_err("%s: failed to map divide register", clk_name);
goto error;
}

parent_name = of_clk_get_parent_name(node, 0);
of_property_read_u32(node, "renesas,width", &width);
clk = clk_register_divider(NULL, clk_name, parent_name,
CLK_SET_RATE_GATE, divcr, 0, width,
CLK_DIVIDER_POWER_OF_TWO, &clklock);
if (!IS_ERR(clk)) {
of_clk_add_provider(node, of_clk_src_simple_get, clk);
return;
}
pr_err("%s: failed to register %s div clock (%ld)\n",
__func__, clk_name, PTR_ERR(clk));
error:
if (divcr)
iounmap(divcr);
}

CLK_OF_DECLARE(h8300_div_clk, "renesas,h8300-div-clock", h8300_div_clk_setup);
147 changes: 147 additions & 0 deletions drivers/clk/h8300/clk-h8s2678.c
Original file line number Diff line number Diff line change
@@ -0,0 +1,147 @@
/*
* H8S2678 clock driver
*
* Copyright 2015 Yoshinori Sato <[email protected]>
*/

#include <linux/clk.h>
#include <linux/clkdev.h>
#include <linux/clk-provider.h>
#include <linux/err.h>
#include <linux/device.h>
#include <linux/of_address.h>

static DEFINE_SPINLOCK(clklock);

#define MAX_FREQ 33333333
#define MIN_FREQ 8000000

struct pll_clock {
struct clk_hw hw;
void __iomem *sckcr;
void __iomem *pllcr;
};

#define to_pll_clock(_hw) container_of(_hw, struct pll_clock, hw)

static unsigned long pll_recalc_rate(struct clk_hw *hw,
unsigned long parent_rate)
{
struct pll_clock *pll_clock = to_pll_clock(hw);
int mul = 1 << (ctrl_inb((unsigned long)pll_clock->pllcr) & 3);

return parent_rate * mul;
}

static long pll_round_rate(struct clk_hw *hw, unsigned long rate,
unsigned long *prate)
{
int i, m = -1;
long offset[3];

if (rate > MAX_FREQ)
rate = MAX_FREQ;
if (rate < MIN_FREQ)
rate = MIN_FREQ;

for (i = 0; i < 3; i++)
offset[i] = abs(rate - (*prate * (1 << i)));
for (i = 0; i < 3; i++)
if (m < 0)
m = i;
else
m = (offset[i] < offset[m])?i:m;

return *prate * (1 << m);
}

static int pll_set_rate(struct clk_hw *hw, unsigned long rate,
unsigned long parent_rate)
{
int pll;
unsigned char val;
unsigned long flags;
struct pll_clock *pll_clock = to_pll_clock(hw);

pll = ((rate / parent_rate) / 2) & 0x03;
spin_lock_irqsave(&clklock, flags);
val = ctrl_inb((unsigned long)pll_clock->sckcr);
val |= 0x08;
ctrl_outb(val, (unsigned long)pll_clock->sckcr);
val = ctrl_inb((unsigned long)pll_clock->pllcr);
val &= ~0x03;
val |= pll;
ctrl_outb(val, (unsigned long)pll_clock->pllcr);
spin_unlock_irqrestore(&clklock, flags);
return 0;
}

static const struct clk_ops pll_ops = {
.recalc_rate = pll_recalc_rate,
.round_rate = pll_round_rate,
.set_rate = pll_set_rate,
};

static void __init h8s2678_pll_clk_setup(struct device_node *node)
{
unsigned int num_parents;
struct clk *clk;
const char *clk_name = node->name;
const char *parent_name;
struct pll_clock *pll_clock;
struct clk_init_data init;

num_parents = of_clk_get_parent_count(node);
if (num_parents < 1) {
pr_err("%s: no parent found", clk_name);
return;
}


pll_clock = kzalloc(sizeof(struct pll_clock), GFP_KERNEL);
if (!pll_clock) {
pr_err("%s: failed to alloc memory", clk_name);
return;
}

pll_clock->sckcr = of_iomap(node, 0);
if (pll_clock->sckcr == NULL) {
pr_err("%s: failed to map divide register", clk_name);
goto error;
}

pll_clock->pllcr = of_iomap(node, 1);
if (pll_clock->pllcr == NULL) {
pr_err("%s: failed to map multiply register", clk_name);
goto error;
}

parent_name = of_clk_get_parent_name(node, 0);
init.name = clk_name;
init.ops = &pll_ops;
init.flags = CLK_IS_BASIC;
init.parent_names = &parent_name;
init.num_parents = 1;
pll_clock->hw.init = &init;

clk = clk_register(NULL, &pll_clock->hw);
if (IS_ERR(clk))
kfree(pll_clock);
if (!IS_ERR(clk)) {
of_clk_add_provider(node, of_clk_src_simple_get, clk);
return;
}
pr_err("%s: failed to register %s div clock (%ld)\n",
__func__, clk_name, PTR_ERR(clk));
error:
if (pll_clock) {
if (pll_clock->sckcr)
iounmap(pll_clock->sckcr);
if (pll_clock->pllcr)
iounmap(pll_clock->pllcr);
kfree(pll_clock);
}
}

CLK_OF_DECLARE(h8s2678_div_clk, "renesas,h8s2678-pll-clock",
h8s2678_pll_clk_setup);

0 comments on commit 7b5bb89

Please sign in to comment.